Navigation Links
Arctic coring expedition continues to yield new clues

For the second time in as many months, the IODP Arctic Coring Expedition (ACEX) is making news with new analysis of ocean-floor sediments. In the Aug. 10 issue of Nature, an article by several of the expedition scientists summarizes their findings: more evidence that the Arctic was extremely warm, unusually wet, and ice-free up to the time the last massive amounts of greenhouse gases were released into the Earth's atmosphere ?a period calculated to have occurred 55 million years ago, and known as the Paleocene/Eocene thermal maximum, or PETM.

Researchers have long recognized that a massive release of greenhouse gases, probably carbon dioxide or methane, occurred during the PETM. Surface temperatures also rose in many places by as much as 15 degrees Fahrenheit in the (relative) geological instant of about 100,000 years.

Arctic sediment samples were largely unavailable until 2004, when ACEX scientists recovered the first deep-ocean sediment samples from beneath the ice-laden waters near the North Pole. ACEX, only the second scientific expedition to be conducted by the Integrated Ocean Drilling Program (established 2003), recovered 339 meters of subseafloor sediment samples.

"Building a picture of ancient climatic events is a lot like putting together a jigsaw puzzle, and what ACEX allowed us to do was fill in a blank section of the PETM picture," said Gerald Dickens, a Rice University geochemist and co-author, who conducted the initial, shipboard chemical analyses of all the ACEX core samples.

"The ACEX cores clearly show that the Arctic got very warm and wet during the PETM," Dickens said. "Even tropical marine plants thrived in the balmy conditions."

In today's oceans, certain species of microscopic plants are known to rapidly multiply and create algal blooms. Dickens said that fossils of these plants ?known only to originate in the tropics before the PETM ?are commonly seen in the ACEX cores. Furthermore, th e chemistry of the organic carbon in the ACEX cores may rule out some earlier theories about what caused the PETM. The diminution of these alternate explanations strongly suggests that an enormous amount of carbon entered the atmosphere at the beginning of the PETM, either from volcanic eruptions, or the melting of oceanic gas hydrates ?mixtures of methane and ice on the seafloor.


'"/>

Source:Integrated Ocean Drilling Program Management International


Related biology news :

1. Grizzlies set to invade high Arctic?
2. Innovative collaboration brings Arctic science into the classroom
3. Census of Marine Life explorers surprised by diversity, density of Arctic creatures
4. Industrial contaminants spread by seabirds in High Arctic, new Canadian study shows
5. Lands surface change on Alaska tundra creating longer, warmer summers in Arctic
6. Displaced songbirds navigate in the high Arctic
7. Scientists to employ Arctic ice and polar bears to protect diversity of worlds crops
8. Arctic expedition will investigate alien-like glacier
9. Record air pollution above the Arctic
10. Pollutant haze heats the Arctic
11. New method confirms importance of fungi in Arctic nitrogen cycle
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/3/2016)... 2016 Vigilant Solutions announces today that the ... Missouri solved two recent hit-and-run cases ... from Vigilant Solutions. Brian Wenberg explains, ... victim was walking out of a convenience store and witnessed an elderly male ... vehicle, striking his vehicle and leaving the scene.  In ...
(Date:2/2/2016)... , Feb. 2, 2016 This ... the bioinformatic market by reviewing the recent advances ... tools that drive the field forward. Includes forecast ... Identify the challenges and opportunities that exist ... and software solution developers, as well as IT ...
(Date:2/2/2016)... Va. , Feb. 2, 2016   ... award from the U.S. Army Research Office and ... the range and sensitivity of the company,s ... Past Accounting Mission and, more generally, defense-related DNA ... DNA phenotyping capabilities (predicting appearance and ancestry from ...
Breaking Biology News(10 mins):
(Date:2/4/2016)... MONMOUTH JUNCTION, N.J. , Feb. 4, 2016 ... critical care immunotherapy leader commercializing its flagship CytoSorb® ... and cardiac surgery patients around the world, announced ... PhD, will present at the Source Capital Group,s ... overview and update on the company.  ...
(Date:2/4/2016)... BEIJING , Feb. 4, 2016 Sinovac ... ), a leading provider of biopharmaceutical products in ... committee of its board of directors received on February ... 3, 2016, from a consortium comprised of PKU V-Ming ... Sinobioway Biomedicine Co., Ltd., CICC Qianhai Development ( ...
(Date:2/3/2016)... 2016  Discovery Laboratories, Inc. (NASDAQ: DSCO ... KL4 surfactant therapies for respiratory diseases, today announced ... inducement award as a component of employment compensation ... President and Chief Executive Officer.  The award was ... 1, 2016 and granted as an inducement material ...
(Date:2/3/2016)... ... February 03, 2016 , ... Aerocom, a ... dedicated to the North American healthcare market. , Aerocom Healthcare, LLC will be ... The company will provide new pneumatic tube systems or expand existing systems within ...
Breaking Biology Technology: